Video Experimental Relacionado
Updated: Jul 19, 2026
08:22
Calibration-free In Vitro Quantification of Protein Homo-oligomerization Using Commercial Instrumentation and Free, Open Source Brightness Analysis Software
Published on: July 17, 2018
Las proteínas sintetizadas in vivo con fluorescencia monoexponencial tienen cinética de desintegración de
Jaap Broos1, Francesco Maddalena, Ben H Hesp
1Department of Biochemistry, Groningen Biomolecular Science and Biotechnology Institute (GBB), and Ultrafast Laser & Spectroscopy Laboratory, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands. j.broos@chem.rug.nl
Journal of the American Chemical Society
|January 8, 2004
Resumen
El 5-fluorotriptófano, un análogo del triptófano, exhibe un decaimiento de fluorescencia monoexponencial en las proteínas, simplificando el análisis de los datos. Esta simplificación permite una medición precisa de las distancias utilizando la transferencia de energía de resonancia (RET) en sistemas complejos de proteínas.
Área de la Ciencia:
- La biofísica es la biofísica.
- Espectroscopia de fluorescencia de proteínas por fluorescencia de proteínas.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La desintegración de la fluorescencia del triptófano en las proteínas es típicamente multiexponencial, lo que complica el análisis de los datos de fluorescencia con resolución temporal.
- Esta complejidad dificulta los estudios que involucran anisotropía, apagadores dinámicos o transferencia de energía de resonancia (RET).
Objetivo del estudio:
- Para investigar la cinética de desintegración de fluorescencia del 5-fluorotriptófano, un análogo isostérico del triptófano, cuando se incorpora a las proteínas.
- Evaluar la utilidad del 5-fluorotriptofano para simplificar las mediciones de distancia en sistemas de proteínas utilizando RET.
Principales métodos:
- Incorporación biosintética del 5-fluorotriptofano en las proteínas.
- Medidas de desintegración de fluorescencia con resolución de tiempo.
- Aplicación de los principios de RET para determinar las distancias en una proteína oligomérica.
Principales resultados:
- El 5-fluorotriptófano exhibe cinética de desintegración de fluorescencia monoexponencial en las proteínas, a diferencia del triptófano nativo.
- El átomo de fluoro en la posición 5 suprime la transferencia de electrones al enlace péptidico, lo que explica la desintegración simplificada.
- Es factible la medición simultánea de múltiples distancias entre el 5-fluorotriptófano y un aceptador RET.
- Las distancias individuales dentro de una proteína oligomérica se resolvieron utilizando 5-fluorotriptófano y un aceptor de RET unido al sustrato.
Conclusiones:
- El 5-fluorotriptofano ofrece un perfil de desintegración de fluorescencia simplificado, lo que facilita una interpretación más directa de los datos de resolución temporal.
- Este análogo permite la medición precisa y simultánea de múltiples distancias de proteínas a través de RET.
- El 5-fluorotriptofano es una herramienta valiosa para los estudios estructurales y dinámicos de las proteínas, particularmente en sistemas complejos.
Videos de Conceptos Relacionados
01:22Protein Folding
Overview
02:15Protein and Protein Structure
Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme can...
A protein's shape is critical to its function. For example, an enzyme can...
01:25Protein Folding
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
01:19Protein Dynamics in Living Cells
Different fluorescence-based techniques are used to study the protein dynamics in living cells. These techniques include FRAP, FRET, and PET.
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
Fluorescent recovery after photobleaching (FRAP) is a fluorescent-protein-based detection technique used to quantify protein movement rates within the cell. This method exposes a small portion of the cell to an intense laser beam. The laser beam causes permanent photobleaching of the fluorophore-tagged proteins in the exposed region. As the bleached...
01:28Protein Denaturation
The function of proteins depends on their native three-dimensional structure, which is dictated by the amino acid sequence of the specific protein. Folding of the polypeptide chain takes place under specific conditions that energetically favor the folded conformation. In contrast, protein denaturation occurs spontaneously under unfavorable conditions that disrupt the integrity of the folded conformation. Thus, the chemical and physical environment of a protein, such as significant changes in pH...
01:26Bacterial Protein Maturation
Bacterial protein maturation is a tightly regulated process that ensures newly synthesized polypeptides achieve correct functional conformations. This maturation involves a series of modifications, folding events, and quality control steps, often assisted by specialized chaperone proteins.N-Terminal ModificationsThe maturation of bacterial polypeptides begins cotranslationally as the polypeptide exits the ribosome. The first amino acid, N-formylmethionine (fMet), is typically modified at the...